"Vivek Chadha" <[EMAIL PROTECTED]> writes:
> "When I attempt to import the CA cert to the smartcard, why does'nt the
> NSS create a 'new' cert in the token store (on the smartcard)? Instead,
> you just see a copy over of the CA cert to the token store"
> 
> I think the reason is that when you attempt to move a CA cert, you do
> not have its corresponding private key and the NSS will not let you
> 'own' the CA cert. The smartcard is a secure storage for only the certs
> that the individual entity owns. The 'public' CA cert is exactly
> that...'public' so there is no reason to move it elsewhere.

hardware token is nominal a secure storage for private key ... from
PAIN

* privacy (sometimes CAIN & confidentiality)
* authentication 
* integrity
* non-repudiation

you are specifically looking at privacy and confidentiality for the
private key.

asymmetric key cryptography is the technology ... what one key of a
key pair encodes, the other of the key pair decodes (differentiated
from symmetric key cryptography where the same key is used for
encoding and decoding).

there is a business process defined called public key, where one of
the keys (of a key pair) is labeled "public" and freely
distributed. The other key is labled "private" and is kept
confidential aned never divulged.

layered on this is another business process called digital signature.
the originator computes a hash of a message, encodes the hash with
their private key. they then transmit the original message and the
attached "digita signature". the recipient decodes the digital
signature with the public key, recomputes the message hash and
compares the two hash values (the recomputed and the decoded). if they
are equal, then the recipient can assume 1) the message hasn't been
altered and 2) "something you have" authentication (aka the sender has
access to and use of the corresponding private key) ... aka from
3-factor authentication

* something you have
* something you know
* something you are

most business operations have long standing and well established
relationship management infrastructures. they use such relationship
management infrastructures to record things about the relationship
(address, current account balance, permissions, etc) as well as
authentication material ... in the past, frequently shared-secret
(mother's maiden name, SSN, pin or password). however, it is also
possible to use well established and long standing relationship
management infrastructures to also record public key as authentication
material. the advantage that public keys have over shared-secrets is
that with shared-secrets people with access to the relationship
management infrastructure can also use the shared-secret
authentication material for impersonation. the public key can only be
used for authentication (and not impersonation). there was a report in
the last year or so that something like 70 percent of account/identity
theft involves insiders.

business processes also have a requirement that their relationship
management repository has *integrity* (from PAIN) .... aka that they
can trust the information contained in the relationship management
repository (in addition, there is frequently *confidentiality(
requirements if the repository contains shared-secret authentication
material, since that information could be used to impersonate).

there are additional business processes which has an original design
point of offline email from the ealy 80s. this has several pieces;
digital certificates, certification authorities, PKI, etc. In the
early 80s, a recipient dialed their local (electronic) post office,
exchanged email and hung up. they now were potentially faced with
processing first time communication from a total stranger (and had no
recourse to local or other information about the total stranger).

The total stranger registers their public key and other information in
a relationship management infrastructure run by a certification
authority. The certification authority then creates specially formated
a digitally signed message called a digital certificate (containing
the registered information). Now a stranger, with first time
communication, creates a message, digitally signs it and sends off the
message, the digital signature and the digital certificate.

first off, a recipient has expended their *trusted* repository to
include the authentication public keys of some number of these
certification authorities. when the recipient receives a first time,
digitally signed message from a total stranger ... with an attached
digital certificate ... they then can use the CA's public key (from
their *trusted* repository) to validate the (digital signature on the)
digital certificate. then they can use the sender's public key from
the digital certificate to validate the message's digital
signature. they they use the additional information contained in the
digital certificate (copied from the certification authority's
relationship management repository) in the processing of first time
communication from a total stranger. this is an alternative to the
recipient already having the stranger's public key directly registered
in the recipient's relationship management infrastructure.

the digital certificate format is sometimes convenient for
transporting CA public keys ... with the objective that they are sent
to a relying party who then can load the associated public key into
their *trusted* relationship repository. they typically aren't digital
certificates in the business process definition since they are
frequently self-signed and the receiving relying party must perform
some other process before deciding to load the associated public key
into their *trusted* relationship repository.

In the early 90s, you were finding some certification authorities
looking at grossly overloading x.509 identity certificates with
personal information (because they weren't able to predict who the
recipients were going to be and/or what their requirements might be
when dealing with total stranger). In such PKI/CA business process,
these recipients are also referred to as relying parties (because they
are relying on the information supplied by the certification
authorities in the digital certificate).

In the mid-90s, you started to see some institutions realizing that
x.509 identity certificates, grossly overloaded with personal
information, represented significant privacy and liability issues.  In
this time-frame you saw some retrenchment to relying-party-only
certificates. These relying-party-only certificates effectively
contained some sort of database lookup index (like an account number)
and a public key. Howevere it is trivial to show that such
relying-party-only certificates are redundant and superfluous i.e.  by
definition, the relying party already has access to all the necessary
information in their relationship management infrastructure.

In some PKI/CA payment initiatives from the mid-90s, they also found
out that such relying-party-only certificates represented severe
payload bloat. The typical payment message size is on the order of
60-80 bytes while the relying-party-only certificate overhead ran
4k-12k bytes. Not only was it trivial to show that such
relying-party-only certificates were redundant and superfluous, but
they also represented a factor of 100 times increase in payload bloat
(which is pretty significant for something not serving any useful
purpose).

-- 
Anne & Lynn Wheeler | http://www.garlic.com/~lynn/
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